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/* Copyright 2013 The Chromium OS Authors. All rights reserved.
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
/* Hardware timer driver API */
#ifndef __CROS_EC_HWTIMER_H
#define __CROS_EC_HWTIMER_H
/**
* Programs when the next timer should fire an interrupt.
*
* The deadline is ahead of the current counter (which may of course wrap) by
* the number of microseconds until the interrupt should fire.
*
* @param deadline timestamp of the event in microseconds
*/
void __hw_clock_event_set(uint32_t deadline);
/* Returns the timestamp of the next programed event */
uint32_t __hw_clock_event_get(void);
/* Cancel the next event programed by __hw_clock_event_set */
void __hw_clock_event_clear(void);
/**
* Get the lower 32-bits of the free-running counter used as clock
*
* The counter resolution must be 1us, since udelay() relies on this.
*
* @return current counter value
*/
#ifdef CONFIG_HWTIMER_64BIT
__override_proto
#endif
uint32_t __hw_clock_source_read(void);
/**
* Override the lower 32-bits of the hardware counter
*
* The new value takes effect immediately and the counter continues counting
* from there, assuming it is enabled
*
* @ts Value to write
*/
void __hw_clock_source_set(uint32_t ts);
/**
* Get the 64-bit value of the free-running counter used as clock,
* only available when CONFIG_HWTIMER_64BIT is enabled.
*
* This function should only be used by common/timer.c or
* chip-specific code, as get_time() abstracts the config option away.
*/
uint64_t __hw_clock_source_read64(void);
/**
* Override the 64-bit value of the free-running counter used as
* clock, only available when CONFIG_HWTIMER_64BIT is enabled.
*
* This function should only be used by common/timer.c or
* chip-specific code, as force_time() abstracts the config option
* away.
*/
void __hw_clock_source_set64(uint64_t timestamp);
/**
* Enable clock to a timer.
*
* @param n Timer number to enable/disable
* @param enable Enable (!=0) or disable (=0) clock to timer
*/
void __hw_timer_enable_clock(int n, int enable);
/**
* Initializes the hardware timer used to provide clock services, using the
* specified start timer value.
*
* It returns the IRQ number of the timer routine.
*/
int __hw_clock_source_init(uint32_t start_t);
/**
* Initializes the hardware timer used to provide clock services, using the
* specified start timer value (CONFIG_HWTIMER_64BIT enabled).
*
* It returns the IRQ number of the timer routine.
*/
int __hw_clock_source_init64(uint64_t start_t);
/**
* Searches the next deadline and program it in the timer hardware.
*
* overflow: if true, the 32-bit counter as overflowed since the last
* call. Goes unused if CONFIG_HWTIMER_64BIT is enabled.
*
* This function is exported from the common timers code as an helper for the
* hardware timer interrupt routine.
*/
void process_timers(int overflow);
/**
* Set up the timer that we will use as a watchdog warning.
*
* Once this has been set up, we will print a warning shortly before the
* real watchdog fires. To avoid this, hwtimer_reset_watchdog() must be
* called periodically.
*
* This is needed since the real watchdog timer (IWDG) does not provide
* an interrupt to warn of an impending watchdog reset.
*/
void hwtimer_setup_watchdog(void);
/* Reset the watchdog timer, to avoid the watchdog warning */
void hwtimer_reset_watchdog(void);
#endif /* __CROS_EC_HWTIMER_H */